Tension mechanism



Patented Fee. is, 1923.

warren er res WILLIAM C. MEYER, OF BEVERLY, MASSACHUSETTS, ASSIGNOR, BY ASSIGN MEETS, T0 UNITED SHOE MACHINERY CORPORATION, OF PATERSO N, NEW JERSEY,

A CORFORATION 01? NEW JERSEY.

TENSION MECHANISM.

Original application filed July 29, 1913, Serial No. 781,785. Divided and this application filed February 1 28, 1916. Serial No. 80,911.

To all whom it may. concern Be it known that '1, WILLIAM C. MEYER, a citizen of the United States, residin at Beverly, in the county of Essex and ommonwea-lth of Massachusetts, have invented certain new and useful Improvements in Tension Mechanism; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to wh1ch it appertains to make and use the same.

The present invention relates to sew ng machines, and more particularly to tension devices for such machines.

The primary object of the invention is to V produce an improved tension device for sewing machines which is simple in construction, strong and durable, which Wlll maintain a substantially constant tension on thev thread during the sewing operation, and in which the tension on the thread may be readily relieved to enable the thread to be drawn freely from the supply.

'With this object in view the invention contemplates the improved constructions and the new combinations of parts set forth in the followin description-and pointed out in the claims, t e advantages of which Wlll be readil understood and appreciated by those ski led in the art.

-The invention is illustrated in the present application as applied to a shoe sewing machine of the so-called McKay type, this application constituting a division of an application Serial No. 781,785, filed July 29th, 1913, on which Patent No. 1,177,581, dated March 28, 1916, was granted, and in which a machine of that type is disclosed. It is to be understood, however, that the invention is not limited to that or any other type of machine, but that it is generally applicable to sewing machines.

The invention will be readily understood from the accompanying drawings illustrating the invention in its preferred form, and the following detailed description of the construction therein shown.

In the drawings Figure 1 is a view in side elevation illustrating the base of a horn of a shoe sewing machine of the McKay type with the tension'devices applied thereto; and Fig. 2 is a view in front elevation partly in section of the construction shown in Fig. 1.

The tension device comprises a tension with a collar or shoulder 10 which engages the outer end of the sleeve 8, and the tension wheel is clamped between the sleeve 8 and 6 and the sleeves are clamped on the shaft by means of a nut 12 threaded on theother end of the shaft. mounted on the end of the sleeve Sand is greferably formed integral with the sleeve. rake shoes 16. and 18 pivoted. together at 20 surround the brake wheel 14 and'are held from turning movement therewith by a screw 22 threaded into the horn which engages 'in a recess between lugs 24 on the brake shoe 18. The brake shoes thus are wholly supported by or float on the pe- The tension wheel A brake wheel 14 is ripheral surface of the brake wheel. 'The brake shoe 16 is provided with a friction pad 26, and the brake shoe 18 is provided with a similar friction pad 28, these pads preferably being made of felt or other fibrous material. The brake shoes are normally held in engagement with the brake wheel 14 by means of a coiled spring 30 surrounding a rod 32 pivotally connected at 34 with the brake shoe'18, and passing through a perforation in a projection on the brake shoe 16, said spring being interposed between the outer face of said projection and a nut 36 threaded on the rod 32. To

enable the thread to be relieved of tension, so that it may be drawn freely about the tension wheel, to permit the removal of the work from the machine, or for any other urpose. alever 38 is pivoted on the end of the shaft 4, and a. second lever 40 is pivoted to the lever 38 upon a stud 42, and is provided with a forwardly extending arm 44 for manipulation by the operator. The lower end of the lever 38 is formed with a cylindrical projection 46, which engages the innor 'face of a lateral projection 34" on the brake shoe 16, and the lower end of the short and tli'"1 upwardly through the horn.

' Meaeaa arm of the lever 4a) is formed with a cylindrical projection 50 which engages the inner face of a lateral projection 51 on the brake shoe 18. The thread '1 as illustrated inthe drawings passes upwardly through the base of the horn 54, about the tension Wheel 2, under a thread truck 56 mounted in the h0g1,

Y pushing the forwardly extendingarm M of the lever 40 downwardly, the levers 38 and 40 are relatively actuated to separate the lower ends of the brake shoes and relieve the pressure of the brake shoes on the brake drum. The tension wheel then is allowed to described a mechanism embodying the in-- mention in its preferred form, What is claimed is: Q

A brake mechanism for thread tension devices having, in combination, a rotary brake Wheel, a pair of brake shoes surrounding the brake Wheel and movable toward and from the same, means for yieldingly pressing the brake shoes into engagement with the brake wheel, and means for moving the brake shoes out of braking relation to the brake wheel to relieve the tension on the thread comprising a lever arranged to actuate one of the brake shoes, a second lever pivotally mounted on the first lever and arranged to actuate the other brake shoe, and a manually movable operating arm formed on the second lever.

WiLrJrAi/i o. MEYER. 

